Electric circuits for producing sparks



April 1942- o. c. SEMONSEN ELECTRIC CIRCUITS FOR PRODUCING SPARKS Filed Sept. 6, 1940 SPHRK COIL BREHKER 5 .5. Fig.7.

m m 9 w 2 7 n 2 8 k 2 w m f x Patented Apr. 28, 1942 OFFICE TS FOR PRODUCING ELECTRIC Cmcm SPARK Otto C. Semonse'n, Bellerose, N. Y. Application September 6, 1940, Serial No. 355,619

16 Claims.

This invention relates to electric circuits for producing sparks such, for example, as are used in ignition systems of internal combustion engines, and the production therein of a plurality of sparks with a single interruption of the electric current.

Present well known spark circuits are designed to produce only a single spark with a single interruption of the electric current and it is common practice to use two entirely separate circuits when it is desired to obtain two sparks.

In order to obtain simultaneous sparks when two separate circuits are used, the interruption of the current in one circuit must be accurately synchronized with the interruption of the current in the other circuit. The use of two circuits is resorted to in order to avoid the increase in electric potential which would be required to obtain two sparks of the desired length in one circuit with a single interruption of the electric current.

I propose to avoid the use of two electric spark circuits, when two sparks are desired, by providing a circuit wherein a plurality of sparks in series can be obtained with a single interruption of the electric current and wherein the plurality of sparks so produced will have greater effectiveness than a single spark produced by an equivalent electric potential under equivalent spark gap conditions.

The primary object of my invention is therefore to provide a new and novel electric circuit for. producing sparks, wherein a plurality of sparks in series can be obtained with a single interruption of theqelectri-c current and wherein the combined length of the plurality of sparks thus obtained will be greater than the length of a single spark produced by the well known circuits using the same electric potential under similar spark gap conditions.

, A further object of my invention is to provide a new and novel method of modifying any well known electric spark circuit so that a plurality of sparks in series can be obtained therefrom with a single interruption of the electric current, the said plurality of sparks having a combined length greater than the lengthof a single spark produced under similar spark gap conditions by the original circuit utilizing the same electric potential.

A further object of my invention is to provide a new and novel electric spark circuit wherein the individual sparks comprising a plurality of sparks in series, which are obtained with a single interruption of the electric current, can be arranged in close proximity to each other.

Another object of my invention is to provide a newand novel electric spark circuit wherein the individual sparks comprising a plurality of sparks in series, which are obtained with a single interruption of the electric current, can be arranged in widely spaced relation.

Another object of my invention is to provide a new and novel electric circuit for producing sparks, wherein a plurality of spark gaps in series are formed by two terminal electrodes and an intermediate electrode, and whereinmeans is provided for bringing the intermediate electrode into a negative condition, with respect to the positive sideof the circuit, thereby causing the electric current to jump each of the gaps comprising the said plurality of spark gaps with each single interruption of the electric current, and wherein the plurality of sparks thus produced will have a combined length greater than the length of the single spark which would be produced by well known spark circuits under similar spark gap conditions by the same electric potential.

Another object of my invention is to provide a new and novel electric spark circuit, wherein a plurality of spark gaps in series are formed by two terminal electrodes and a plurality of intermediate electrodes, and wherein means is provided for creating a negative potential in each of the intermediate electrodes, thereby causing the electric current to jump each of the gaps comprising the said plurality of spark gaps with a single interruption of the electric current, and

wherein the plurality of sparks thus produced will have a combined length greater than the length of the single spark which would be produced by wellknown spark circuits, under similar spark gap conditions, utilizing the same electric potential. 1

Another object of my invention is to provide a new and novel electric spark circuit, wherein a plurality of spark gaps in series are formed by two terminal electrodes and an intermediate electrode in which a negative potential can be created by means connected thereto, and wherein means is provided for limiting the amount of current which can flow from the intermediate electrode through the means provided for creating a nega tive potential therein. 1

Another object of my invention is to provide a method of modifying well known alternating current electric spark circuits so that such a circuit when so modified will produce a plurality of sparks in series having a combined length greater than the length of the single spark which would be produced under similar spark gap conditions by the original circuit utilizing the same electrical potential.

By terminal electrode is meant the instrum-entality or device which, regardless of its form or the material from which it is made, forms, in an electric spark circuit, the terminus of a side of the circuit at the point where it is desired to create a spark, and from which, or to which, the current passes in the form of a spark.

By intermediate electrode is meant, regardless of its form or the material from which it is made, an instrumentality or device interposed between .the terminal electrodes of an electric circuit for producing sparks, thereby forming a plurality of spark gaps in series, and to which, or from which, the current will pass in the form of a spark.

' The terms positive and negative as used herein in connection. with the high tension portion of a spark circuit refer to the relative electric potentials of the sides of the circuit with respect to the current which crosses a spark gap in the form of a spark.

The accompanying drawing illustrates simple and preferred forms of my invention, it being understood however that no limitation is necessarily made to the precise details shown therein, but that alterations and modifications within the scope of the appended claims may be resorted to when desired.

In the drawing: 7 V

Fig. 1 illustrates diagrammatically a simple electric'spark circuit which includes one preferred form of my invention. In this circuit a resistance is connected between the intermediate electrode and the negative side of the circuit so that it is in parallel with the spark gap formed by the intermediate electrode and the negative terminal electrode.

Fig. 2 is a diagrammatic illustration of another preferred form of my invention in which a choke coil is connected between the intermediate electrode and the negative side of the circuit so that it is in parallel with the spark gap formed by the intermediate electrode and the negative terminal electrode.

Fig. 3 is a diagrammatic illustration of another preferred form of my invention in which a condenser is connected between the positive side of the circuit and the intermediate electrode so that it is in parallel with the spark gap formed by the positive terminal electrode and the intermediate electrode.

Fig. 4 illustrates diagrammatically a form of my invention in which the spark gaps are arranged in widely spaced relation.

Fig. 5 illustrates diagrammatically a form of my invention in which a condenser is connected between the positive side of the circuit and the, intermediate electrode and a resistance is connected between the intermediate electrode and the negative side of the circuit.

Fig. 6 is a diagrammatic illustration of a form of my invention in which the intermediate electrode is connected to both sides of the circuit by means of condensers.

Fig. 7 is a diagrammatic illustration of a. form Ofmy invention in which three spark gaps are formed by two terminal electrodes and two in-- termediateelectrodes.

Referring to thedrawing, wherein similar reference characters designate corresponding parts throughout the several views, it will readily be seen that in the various forms of my invention a plurality of spark gaps in series are formed by two terminal electrodes and one or more intermediate electrodes, and that the intermediate electrodes are connected in the circuit in such a manner that a negative potential can be created therein.

In Fig. 1, which illustrates a simple and well known electric circuit for producing sparks which hasbeen modified by my method of producing a plurality of sparks in series with a single interruption of the electric current, is shown a storage battery I6 supplying energy to theprimary of the spark coil H. The electric current flowing through the primary of the spark coil is mechanically interrupted by the breaker I8. The positive side of the secondary of the spark coil I! is connected to the terminal electrode II, and the negative side is connected to the terminal electrode I 2. The intermediate electrode I3 is connected to one side of the resistance I9 and the other side of the resistance is connected to the negative side of the circuit, at a point 20, between the terminal electrode I2 and the spark coil I'I. As the intermediate electrode I3 is connected to the negative side of the circuit by means of the resistance I9 the intermediate 1 electrode will be negative in potential immediately prior to the instant the electric current passes, in the form of a spark, from terminal electrode II, across the spark gap I4, to the intermediate electrode I3. As the intermediate electrode 13 is negative in potential prior to the instant the current jumps the spark gap I4, the resistance of the said gap to the passage of the current is substantially the same as for a gap of equivalent length in the ordinary single spark gap circuit. Therefore the gap I4 can be fixed at any length desired up to the limit of the capacity of the spark coil I! to cause the current to cross the said gap under any given spark gap conditions. After the current has crossed the gap [4 the intermediate electrode I3 will have a positive potential which will cause the current to pass from the intermediate electrode to the negative side of the circuit. As the resistance I9 is connected in parallel with the spark gap.

I5 part of the current will pass through the said resistance and part of it will cross the said spark gap in the form of a spark, provided the potential in electrode I3 is not reduced, by losses due to leakage and the flow of current through resistance I9, below the level-required to cause the current to cross the gap I5. It can therefore be readily seen that the length of the gap I5, for any given spark gap condition, will be limited by the potential which existed at the ter minal electrode II, prior to the passage of the current across the gap I4, reduced by the loss resulting from the crossing of the said gap I l, and further reduced by the losses due to leakage and the flow of current through resistance I9. It can further be readily seen and understood that the greater the resistance of the resistance I9 the lower will be the loss therethrough, and therefore the greater the length at which the gap I5 can be fixed, within the capacity of the potential in electrode I3 to cause the current to cross the said gap. It can also be readily seen that the resistance of the resistance I9 is limited by the requirement to reduce electrode I3 to a negative potential after the current has crossed the gap I so that a subsequent current impulse can cross the gap I4.

Another form of my invention is shown in Fig. 2, which illustrates the spark gap portion of an electric spark circuit. In Fig, 2 the terminal electrode II is indicated as being on the positive side of the circuit andthe terminal electrode I2 is indicated as being on the negative side. 1 One side of the choke coil 2| is connected to the intermediate electrode I3 and the other side to the negative side of the circuit at a point 20. This arrangement is similar to the one shown in Fig. 1 and functions in a similar manner excepting that the choke coil 2| has been substituted for the resistance I9 and therefore that portion of the current flowing from the intermediate electrode I3 through the choke coil 2| to the negative side of the circuit is limited by the inductance of the said choke coil, instead of by the resistance of the resistance I9 as illustrated in Fig. 1 and explained in connection therewith.

The spark gap portion of an electric spark circuit including another form of my invention is shown in Fig. 3. In this form a condenser 22 is connected in parallel with spark gap I4, one side of the said condenser being connected to the positive side of the circuit at a point 23 and the other side to the intermediate electrode I3.

The arrangement of the terminal and intermediate electrodes is similar to that shown in Fig. 1. In this form of my invention a negative potential is created in the intermediate electrode I3 by the well known property of condensers to offset a positive potential on one plate by a negative potential on the other plate. Therefore it can be readily seen and understood that when an electric current flows into the terminal electrode II a portion of the saidcurrent will fiow into and charge the condenser 22, thereby creating a negative potential in the intermediate electrode I3. Having thus created a negative potential in the said intermediate electrode the current will cross the gaps I4 and I5 as described in connection with Fig. 1. It can readily be seen that a drop in potential will occur in the passage of the current from electrode II to electrode I3 by reason of the crossing of the gap I4 and by reason of leakage and losses in the charging and discharging of the condenser 22, and therefore that the capacity of the said condenser is limited by the permissible loss therethrough.

In Fig. 4 is shown a form of my invention similar to that shown in Fig. 1, excepting that the spark gaps I4 and I5 are spaced a substantial distance from each other through the use of two intermediate electrodes, I3 and 24, which are spaced a substantial distance from each other and connected together in such a manner that the current can readily flow from electrode I3 to electrode 24. A negative potential is created in electrode I3 through the use of resistance I9 in a manner similar to that described in connection with Fig. 1.

In Fig. 5 is shown a form of my invention which combines in one circuit the functions of the condenser 22 as shown in Fig. 3 and the resistance I9 as shown in Fig. l and described respectively in connection with the said figures.

In Fig. 6 is shown a form of my invention in which one side of a condenser 22 is connected to the intermediate electrode I3 and the other side is connected, at a point 23, to the side of the circuit terminating at electrode II, thereby connecting the said condenser 22 in parallel with spark gap I4. A similar condenser 25 is connected in parallel with spark gap I5 by connectin-g one side thereof to the intermediate electrode I3 and connecting the other side, at a point 26, to the side of the circuit terminating in electrode I2. In addition to advantages similar to those described for the other forms of my invention this form has the advantage that either side of the circuit may be used as the positive side, or if desired alternating current may be used, as a negative potential will be created, in the intermediate electrode I3 by the functioning of condenser 22 when electrode II is positive and by the functioning of condenser 25 when electrode I2 is positive.

In Fig. '7 is shown a form of my invention in which two intermediate electrodes are used, thereby forming three spark gaps in series. A negative potential will be created in the intermediate electrode I3, through the functioning of resistance I9 in a manner similar to that described in connection with Fig. l, and a negative potential will be created in intermediate electrode 21 in a similar manner through the functioning of resistance 30 as one side of the resistance 30 is connected to electrode 21 and the other side to the negative side of the circuit at a point 3I. Therefore it will be readily seen that a current will cross the spark gap I4, from the positive electrode I I to the intermediate electrode I3, as electrode I3 will have a negative potential prior to the crossing of the gap I I by the said current. The current will then cross spark gap 28 as intermediate electrode 21 will have a negative potential and electrode I3 wil have a positive potential after the current has crossed gap I4, and similarly the current will then cross spark gap 29, from electrode 2'! to electrode I2 which is the terminal electrode on the negative side of the circuit. While Fig. '7 shows a circuit with three. spark gaps it is obvious that the principle illustrated therein is not limited to three spark gaps and that additional intermedi-. ate electrodes could be introduced, thereby providing additional spark gaps.

The amount of resistance, inductance or capacity required to create the proper negative condition in the intermediate electrode of a circuit modified in accordance with my invention is widely variable and depends upon the characteristics of the circuit and the result desired. For circuits similar to that illustrated in Fig. 1 the amount of resistance is of a relatively high order, as the flow of current through the resistance must ordinarily be reduced to a minimum. For such a circuit using an ordinary six volt ignition coil the resistance would be of the order of 300,000 ohms. The amount of capacity required in a circuit similar to that illustrated in Fig. 3 is of a relatively low order. For a circuit using an ordinary six volt ignition coil the capacity of the condenser would be of the order of .0002 microfarad.

From the foregoing descriptions of some forms of my invention it will be seen that I have provided a new and novel electric circuit for producing sparks, wherein a plurality of sparks in series can be produced with a single current impulse and the said plurality of sparks will have a combined length greater than the length of the single spark which would be produced by well known spark circuits utilizing the same electric potential under similar spark gap conditions.

It will also be seen that I have provided a new and novel method of modifying well known electric spark circuits so that a plurality of sparks in series may be obtained from such a modified circuit and the said plurality of sparks will have a combined length greater than the length of the single spark obtained from the original circuit, with a single current impulse, utilizing the same potential under similar spark gap conditions.

It will further be seen that I have provided a new and novel electric spark circuit wherein the individual sparks comprising a plurality of sparks in series which are obtained with a single impulse of the electric current can be arranged in either closely or widely spaced relation.

It will be seen that I have provided a new and novel electric circuit for producing sparks, wherein a plurality of sparks in series can be obtained with a single current impulse through the formation of a plurality of spark gaps by means of one or more intermediate electrodes in which a negative condition can be created with respect to the positive side of the circuit.

It will also be seen that I have provided new and novel electric spark circuits in which means is provided for limiting the amount of loss in electric potential resulting from the means employed to create negative potentials in the intermediate electrodes used to form a plurality of spark gaps in the said circuits.

It will also be seen that I have provided a new and novel electric spark circuit, in which a plurality of sparks in series can be obtained, with one impulse of an electric current, by means of an intermediate electrode in which a negative potential can be created, and which is adapted for the reversal of the positive and negative poles, and in which alternating current can be used.

It will be further seen and understood from the foregoing description of some preferred forms of my invention that any high tension source of electric current may be used and that various arrangements of the spark gaps, and various arrangements of the instrumentalities for creating negative potentials in the intermediate electrodes and for limiting th flow of current therethrough, and various combinations thereof, other than those shown and described may be employed without departing from the scope of my invention.

Having thus described my invention and pointed out the new and novel features therein, what I claim is:

1. A method of modifying an electric circuit for producing sparks, whereby a plurality of sparks in series can be produced therein with a single interruption of the electric current, which consists of interposing an intermediate electrode between and spaced from the terminal electrodes, thereby forming in the said circuit a plurality of spark gaps in series, and providing means for bringing the intermediate electrode into a negative condition with respect to the positive side of the circuit. 1

2. A method of modifying an electric circuit for producing sparks, whereby a plurality of sparks in series can be produced therein with a single interruption of the electric current, which consists of forming therein a plurality of spark gaps in series by means of a plurality of terminal electrodes and an intermediate electrode, providing means for bringing the intermediate electrode into a negative condition with respect to the positive side of the circuit, and providing means for limiting the flow of current through the means provided for bringing the intermediate electrode into said negative condition.

3. A method of modifying .an electric current for producing sparks so that the resistance to the passage of the current across the space between the terminal electrodes is reduced, which consists of providing means for creating a negative condition, with respect to the positive side of the circuit, in the said space at a point between and spaced from the said terminal electrodes.

4. An electric circuit for producing a plurality of sparks in series with a single interruption of the electric current, which consists of a plurality of terminal electrodes joined by electrical conductors to a source of electrical energy of sufficient potential to produce the said plurality of sparks with a single interruption of the electric current, means for interrupting the flow of the current, an intermediate electrode interposed between and spaced from the terminal electrodes, thereby forming a plurality of spark gaps in series, and means for bringing the intermediate electrode into a negative condition with respect to the positive side of the circuit.

5. An electric circuit for producing a plurality of sparks in series with a single interruption of the electric current, which consists of a plurality of terminal electrodes joined by electrical conductors to a source of electrical energy of suincient potential to produce the said plurality of sparks with a single interruption of the electric current, means for interrupting the flow of the current, an intermediate electrode interposed between and spaced from the terminal electrodes, thereby forming a plurality of spark gaps in series, means for bringing the intermediate electrode into a negative condition with respect to the positive side of the circuit and means for limiting the flow of current through the means provided for bringing the intermediate electrode into the said negative condition.

6. An electric circuit for producing sparks, which consists of a spark gap formed by a plurality of terminal electrodes joined by electrical conductors to a source of electrical energy of sufficient potential to produce the said spark, means for interrupting the flow of current, and means for creating a negative condition, with respect to the positive side of the circuit, in the said gap at a point between and spaced from the said terminal electrodes.

7. A method of modifying an electric circuit for producing sparks, whereby a plurality of sparks in series can be produced therein with a single interruption of the electric current, which consists of interposing an intermediate electrode between and spaced from the terminal electrodes, thereby forming in the said circuit a plurality of spark gaps in series, .and providing means for creating a condition of potential with respect to the intermediate electrode which will cause the current to pass from a terminal electrode to the intermediate electrode and from the intermediate electrode to the other terminal electrode.

8. An electric circuit for producing a plurality of sparks in series with a single interruption of the electric current, which consists of a plurality of terminal electrodes joined by electrical conductors to a source of electrical energy, means for interrupting the flow of current, an intermediate electrode interposed between and spaced from the terminal electrodes, thereby forming a plurality of spark gaps in series, and means for bringing the intermediate electrode into a negative condition with respect to the positive side of the circuit, said means being adapted to. limit the loss ot current therethrough,

9. A method of modifying an electric circuit for producing sparks, whereby a plurality of sparks in series can be produced therein with a single interruption of the electric current, said sparks having a combined length greater than the length of a single spark which can be produced by the same electric potential under similar spark gap conditions, which consists of forming therein a plurality of spark gaps in series by means of a plurality of terminal electrodes and an intermediate electrode, and providing means ior bringing the intermediate electrode into a negative condition with respect to the positive side of the circuit.

10. An electric circuit for producing a plurality of sparks in series and in spaced relation with a single interruption of the electric current, which consists of a plurality of terminal electrodes joined by electrical conductors to a source of electrical energy, means for interrupting the flow of the said plurality of sparks can be produced with the current flowing through the circuit in either direction, which consists of interposing an intermediate electrode between and spaced from the terminal electrodes, and providing means for bringing the intermediate electrode into a negative condition with respect to whichever side of the circuit may be positive prior to the passing of the current from a terminal electrode to the intermediate electrode.

12. An electric circuit for producing a plurality of sparks in series, which consists of a plurality of terminal electrodes joined by electrical conductors to a source of electrical energy, an intermediate electrode interposed between and spaced from the terminal electrodes, and means for utilizing a portion of the current to bring the intermediate electrode into a negative condition with respect to the positive side of the circuit.

13. An electric circuit for producing a plurality of sparks in series, which consists of a plurality of terminal electrodes joined by electrical conductors to a source of electrical energy, an intermediate electrode interposed between and spaced from the terminal electrodes, and means for bringing the intermediate electrode into a negative condition with respect to the positive side of the circuit and through which a portion of the current can pass from the intermediate electrode to the negative side of the circuit.

14. An electric circuit for producing a plurality of sparks in series, which consists of a plurality of terminal electrodes joined by electrical conductors to a source of electrical energy, an intermediate electrode interposed betwen and spaced from the terminal electrodes, thereby forming a plurality of spark gaps in series, and an electrical resistance, one end of the said resistance being electrically connected to the intermediate electrode and the other end being electrically connected to the negative side of the circuit.

15. An electric circuit for producing a plurality of sparks in series, which consists of a-plurality of terminal electrodes joined by electrical conductors to a source of electrical energy, an intermediate electrode interposed between and spaced from the terminal electrodes, thereby forming a plurality of spark gaps in series, and an electrical choke coil, one end of the said choke coil being electrically connected to the intermediate electrode and the other end being connected to the negative side of the circuit.

16. An electric circuit for producing a plurality of sparks in series, which consists of a plurality of terminal electrodes joined by electrical conductors to a source of electrical energy, an intermediate electrode interposed between and spaced from the terminal electrodes, thereby forming a plurality of spark gaps in series, and an electrical condenser, one side of the said condenser being electrically connected to the intermediate electrode and the other side being electrically connected to the positive side of the circuit.

OTTO C. SEMONSEN. 

